41. Space Center – Houston, Texas
Who wouldn’t want to visit the place at the heart of space travel? The Space Center in Houston is the official visitor center for NASA and is also the home of NASA Mission Control. Admission allows you to look at over 400 artifacts from space, including some of the hardware that was designed and built to take humans into space (via Oyster). Many other displays and exhibits are going on too, depending on the time of year (via Oyster).